The Dynamics of global urban expansion

This study examined the dynamics of global urban expansion by comparing data and satellite images from two periods measuring urban extent and expansion as well as by calculating the average density of the built-up area. After testing ten econometric models, and testing several hypotheses postulated by neoclassical theories of urban spatial structure, the central message of this study is quite clear: Developing country cities should be making realistic-yet minimal-plans for urban expansion, designating adequate areas for accommodating the projected expansion, investing wisely in basic trunk infrastructure to serve this expansion, and protecting sensitive land from incursion by new urban development.

The study examined the dynamics of global urban expansion by defining a new universe of 3,943 cities with population in excess of 100,000 and drawing a stratified global sample of 120 cities from this universe. Data for 90 cities out of the global sample of 120 is presented and analyzed in this report.